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arXiv · hep-ph/9809413

Double Spin Asymmetries in P-wave Charmonium Hadroproduction

Wolf-Dieter Nowak·Avto Tkabladze
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Abstract

We discuss the double spin asymmetries in P-wave charmonium hadroproduction with non-zero transverse momenta at fixed target energies, $\sqrt{s}\simeq40$ GeV, within the framework of the NRQCD factorization approach. The size of the asymmetries and the projected statistical errors in a future option of HERA with longitudinally polarized protons scattering off a polarized target (HERA-$\vec N$) are calculated. Measurements of the $χ_{c1}$ and $χ_{c2}$ decays into dilepton plus photon should allow to distinguish between different parametrizations for the polarized gluon distribution in the proton. At higher energies ($\sqrt{s}=200$ GeV) the situation appears less favourable with the presently envisaged integrated luminosities of the polarized RHIC collider.

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Wolf-Dieter Nowak, Avto Tkabladze. 1998-09-16. Double Spin Asymmetries in P-wave Charmonium Hadroproduction. https://doi.org/10.1016/s0370-2693(98)01289-1

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